NOTE SUL RESTAURO DELLA LACCA GIAPPONESE
This question has been exercising my mind, both as a teacher and as a private conservator, for the last couple of years and I thought it might be interesting to get some of my musings on paper.
Historically speaking, Western and Eastern approaches to the restoration and conservation of lacquerwork have been very different. In the West
‘reversibility’ has been a fundamental principle, firmly lodged in ethics codes, although phrases like ‘reversible when possible’ and ‘retreatability’ now appear. This usually meant that lacquer was restored either using modern materials such as Paraloid (Acryloid in USA) resins, poly vinyl alcohols and acetates, phenolic micro-balloons and the like, or traditional resins and bulking agents found in japanning and furniture finishing such as animal glues, chalk and shellac. In the East, lacquer was invariably restored with more lacquer by ‘lacquer masters’: makers more than conservators by trade. To confound matters, there was very little communication between the two camps.
Today, things are changing. There is much greater dialogue between East and West, with Eastern masters invited to contribute to major projects like the V&A’s Mazarin Chest. This is entirely for the good and has lead to a certain softening of position on both sides: Eastern Masters now happier to contemplate the use of modern, reversible materials and Western
Conservators less phobic about the use of Urushi.
For the moment, leaving aside technical, aesthetic and ethical aspects, one must deal with the health and safety issue. Urushi is tapped from the lacquer or ‘varnish’ tree (rhus verniciflua, predominantly), purified and then used. The tree is related to poison ivy and by nature toxic. Human reaction to exposure varies from nothing at all to quite acute skin reaction and generally feeling rather unwell. Statistics are unclear, usually claiming about 1% of Westerners likely to be allergic but from most groups of ten, one always seems affected which suggests 10%.. Even so, one might reasonably expect safe working practice and no skin contact

with the lacquer; use of protective clothing and gloves, masks even.
Nonetheless, it would be a brave teacher indeed who could guarantee a group of twenty-something twenty-somethings wouldn’t manage to spatter themselves or a neighbour with lacquer. This scenario throws up a sticky legal and moral situation for a college. Perhaps one can ask all students to sign a disclaimer along the lines of ‘I agree that by using this resin it is possible that I’ll end up in bed for six weeks’ but if that should happen and they miss all their exams and project work deadlines a college should feel remorse at the very least and possibly severely out of pocket as a result of legal action. I am still arguing with myself about the use of Urushi at my university for this reason alone.
The common procedures for lacquer repair are filling losses, adhering loose lacquer, retouching lost decoration and refinishing in order to resaturate the colour and provide gloss. Thankfully, many museums have decided to forego many such procedures, opting for strict conservation and minimum intervention. Antique dealers have not; especially those selling to the American market. The demands of the trade put severe pressure on private restorers to ‘come up with the goods’ by whatever method. Many of those restorers working on lacquer are furniture restorers and gilders by training. As such, they use what they know and feel comfortable with: gesso for fills, animal glues for sticking, shellac and or wax for finishing.
I still read papers where people refinish lacquer with shellac and my heart sinks. Equally, there is many a private practice using oil paint for retouching.
The argument for most of these materials’ use is that they are ‘tried and tested’ and that the practitioner is competent in their use. I have tried and tested them on lacquer and they are far from appropriate.
Those attempting to act more ethically use a variety of materials gleaned from a variety of reliable sources on how to conserve lacquer: modern synthetic resins, primarily acrylics, bulked with phenolic micro-balloons or glass spheres for filling; Paraloid resins or Beva resin or film for sticking; a variety of acrylic solutions or dispersions for finishing, with
Primal (Acrysol in US) WS24 being a particular favourite. Most Oriental lacquer masters have very little enthusiasm for any of these materials and would use lacquer bulked with burnt earths for filling, the correct lacquer for retouching with the appropriate metal foils and powders and the finest lacquer for re-finishing. Many Western conservators have decided to do

the same, not least, I suspect, because it carries a certain kudos, mystique even, with most antique dealers.
When I first started working with Urushi lacquer I got rather excited. I love playing with resins, historic and modern, and lacquer has to be top dog. Immediately one feels like a proper craftsperson, imbued with all the historic and cultural aspects of this prized sap; there is the additional frisson that this beautiful poison might put you in the sick bed for some while. (When I did my first skin test I started to itch all over and saw red marks appearing over my arm. Fortunately, these were tricks of an expectant mind and have not been repeated and nor have I shown any actual reaction).
In my dual capacity of teacher who likes to experiment and ‘empower’ students and private conservator who has a penchant for feeding a family of five, I started to experiment with lacquer, applying it to a number of small lacquer boxes found on ebay. I became rather good at working with it, adopting an ‘its hardly rocket-science’ attitude. I made it known to antique dealers that I was someone, a very rare bird, I added, that could work with genuine Urushi.
The problem with most historic ingredients like shellac is that they darken quickly and can flake off lacquer objects with alarming speed. Getting them off again can pose unacceptable risk to a lacquer object, so here is my rule number one: never use shellac for refinishing a lacquer object.
There is possible justification for its use on adjacent repaired areas.
Micro-crystalline wax is still a favourite for refinishing lacquer but there is still debate as to whether an Urushi repair can ever be successfully carried out over a partially removed layer of wax. One can become quite clever in the manipulation of modern resins such as Paraloid B72 and Primal
WS24. Nonetheless, plastic coatings, however thin and beautifully applied, tend to look like what they are: plastic coatings. This is not a good thing from an aesthetic point of view. There is also the vital consideration, often overlooked when refinishing with whatever material, that decoration on lacquer objects is often supposed to appear matt relative to surrounding lacquer; re-finish wholesale and this delicate balance is immediately lost, usually irretrievably.

So, if modern and traditional materials don’t quite fit the bill, surely that leaves lacquer? No, although I initially thought so. Carried away by my enthusiasm for working with Urushi, and tempted by its likely reward, I thought I could do away with reversibility and immerse myself in the culture and mystique of self-taught lacquer master. Then I changed my mind. Use of lacquer is indeed not rocket science and there is a reasonable case for it when simply providing a microscopically thin re-saturating layer (or layers) of the finest transparent lacquer. Nonetheless,
‘transparent’ lacquer is not completely transparent (all Urushi darkens upon exposure to the air) and one must apply it before considering any retouching any matt gold powders, say, for fear of destroying the matt/gloss balance. There is also evidence that newly applied lacquer will age differently to the old, causing future problems.
There is something delicious about retouching lacquer with Urushi and gold powders but one must not let arrogance or plain foolhardiness cloud judgement. I am pretty good at retouching, but would not presume the eye or hand of a lacquer master with a lifetime’s experience nor the exact stylistic mindset of someone working in 1830. Get it wrong with lacquer, let it cure, and you have a mountain of unjustifiable reversibility problems.
My initial rush and self-importance over, I now have strict ideas about lacquer restoration:
Clean by following conventional solvent wisdom – use non-polar solvents
(Stoddard solvent, White Spirit, Xylene) before polar (water, saliva, alcohol) and don’t use very polar solvents (acetone) at all.
Don’t use traditional water or alcohol based (polar) resins. So, no shellac, traditional gesso, animal glue. My exception to this is to use fish glue, carefully, to stick detached lacquer flakes, mainly because it works where so many modern resins don’t.
Fill with something with less water content than traditional gesso. Flavour of the year is Flugger (a butyl methacrylate, water and chalk proprietary
Danish filler), used extensively by museums and private practice; it has long been a favourite of mine too.

Retouching. Extensive trials lead me to use Aquacryl (Lascaux, waterresoluble acrylic) clear medium with powder pigments, gouache, watercolour and, most importantly, genuine Japanese gold powders.
These are finer and more suitable for lacquer work than European variants. I have really gone off mica powders – they are grainy, often the wrong shape and colour, although I know many people still like and use them. Given the amount used, I don’t think cost should deter people from using Japanese powders. Ethically, a white spirit based resin – Paraloid
B67 or MS2A – would be better (more easily reversed) than Aquacryl but
I’m not a huge fan of their use on lacquer, regardless of their efficacy for canvas paintings. They tend to make grainy paints with some powders and not produce as fine a line when applied to lacquer as the Lascaux product.
Also, Aquacryl can take a light burnish where that is appropriate.
Refinish with caution: one may consider Paraloids, Primals, microcrystalline wax, Urushi itself and a variety of others. All are ethically, technically or aesthetically challenged.
I hope these ramblings have provided food for thought from both technical and ethical viewpoints. If nothing else, they should add fuel to the debate.
It is hugely encouraging that this debate is taking place. I end by cautioning any Western restorers who discover this exotic material to tread with extreme caution. It may impress people in the antiques trade or a group of under graduates but it is not that easy to use and you invariably won’t know you’ve got it wrong until its too late. It is intrinsically irreversibly once cured and, at the very least, might confine you to your sick bed.
Brief Case Study:
Illustrated below is a before and after photograph of a Chinese Export lacquer jewellery box c1830.

Treatment:
The box was covered in aged, discoloured shellac. Rather than use the more conventional alcohol to remove it, trials confirmed that a methylene chloride stripper was more effective, quicker and although intrinsically harsher, more benign in this case – the abrasive effect of numerous solvent applications can be far more damaging than a ‘short, sharp shock’. These types of solvent work well on lacquer, try them on pen-work or japanning and you’re in for total disaster!
There was a large hole in the lid and various other losses. Infilling was done with Flugger and additions of ivory black.
Retouching was carried out with Aquacryl and Japanese reddish and greenish gold powders (Junkin-Keshifun).

A thin coat of microcrystalline wax was applied for final balance and protection – it is not my intention to carry out an Urushi repair on this box.